A new saponin from Acanthopanax koreanum with anti-inflammatory activity

Twelve saponins were isolated from the leaves of Acanthopanax koreanum, including one new lupane-type triterpene glycoside, named acankoreoside R (1), together with 11 known triterpenoid saponins (2-12). Their structures were elucidated by 1D and 2D nuclear magnetic resonance (NMR), mass spectroscopic data (MS). All of the fractions and isolated saponins were evaluated for anti-inflammatory activities in lipopolysaccharide (LPS)-stimulated bone marrow-derived dendritic cells (BMDCs) by ELISA. Among them, compounds 1-5, 7, 10, and 12 showed strong inhibitions towards interleukin-12 (IL-12) production with IC₅₀ values ranging from 1.59 to 5.46 µM. Other compounds were weak or inactive toward IL-12 p40 production.